Category Archives: Biological Sciences

The bugs in your guts are making you fat.

Generally when we think “bacteria” and “guts”, we think of nasty things like food poisoning or the stomach flu. But in reality, there are large amount of bacteria living in our lower digestive system – what scientists call the Gut Microflora. In fact, some recent research has shown that the bacteria living in our guts aren’t simply enjoying a tenant-landlord relationship; in fact, they may actively contribute to our overall health. A good example of this is the much-hyped “probiotics” recently being promoted as the new “superfood” essential to successful diets. As Yogurt companies have been advertising left and right,   “an exclusive probiotic culture … has been shown to survive passage through the digestive tract in sufficient amounts for Activia to help regulate the digestive system”. But is there any truth to this?

Some research has indicated that certain species of bacteria may contribute to the overall efficiency of energy extraction and affect overall levels of host obesity;  and in fact, studies in mice have shown that mice with differing levels of obesity has different compositions in their gut microflora, showing quite the correlation between bacterial colonies in the gut and obesity. This begs the question, Would changing the bacteria help make you skinnier?

 Scientific American-Volume 310, Issue 6. "How Gut Bacteria Help Make Us Fat and Thin"

Scientific American-Volume 310, Issue 6.
“How Gut Bacteria Help Make Us Fat and Thin”

 

 

 

 

 

 

 

 

 

To make a long and complicated answer short, We don’t know.  Though there has been trials done confirming the short-term effects on things related to obesity, so far no study has proven effective, as the gut microflora is a complicated subject with many facets to watch.  That being said, There are current studies in the works, so keep an (critical) eye on your news feed, and feel free to eat all the yogurt you’d like.

– James L.

 

 

 

Collagen cannot be absorbed through skin!

The desire to stay youthful for many women has been consistent; hence keeping a youthful skin has also been a consistent concern. Thus it really disturbs me that the beauty market nowadays targets and takes advantage of these worries to sell skin products with false advertisements at shockingly expensive prices. FALSE advertisement, that’s right. Many different brands flaunt their new line of creams with this magical molecule “collagen,” which can apparently make skin plumped-up, smoother, and younger.

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This is complete nonsense. It is a cold hard fact that collagen molecules are just too large to be absorbed through tiny pores of skin. It will have no benefits to skin when it is being applied in such way. Let’s take a closer look at collagen.

Collagen

Collagen

 

Collagen itself is a protein present in all body’s organs and connective tissues and mainly functions to sustain tendons, cartilage, and skin. It provides firmness and elasticity to skin and thus making it true that increasing collagen levels in body will increase the chance of skin staying more youthful. This is the scientific reasoning behind those false advertisements.

However, it is critical to note that this is only true when we increase level of collagen by eating the right, healthy food or by taking collagen supplements, but not by applying those collagen-containing creams on our faces. Like I said before, collagen molecules are too large to be absorbed through the pores of our skin, and even if the skin could absorb them, we have to remember that collagens are proteins naturally made inside our body. They would be completely “dead” and inactive by the time we rub them onto the skin. The only reason why your expensive collagen cream feels nice is because it gives cream its consistency.

Let us not forget that including collagen in skin care products is just another way of marketing. This had been proven quite a while ago, but many still seem to be unaware of this. So remember this and do not waste your time and money on collagen-containing creams, everyone! Why don’t we all try eating more soy products, vegetables, and fruits instead?

 

By Sunny Sohn

Images/Video Sources:

Collagen image: http://eyeonicr.wordpress.com/2011/07/06/soft-tissues-and-logical-fallacies/

Fruits and Vegetables image: http://www.lifehack.org/articles/lifestyle/20-incredible-facts-about-eating-fruits-and-vegetables-that-you-probably-didnt-know.html

 

Geoengineering

I was first introduced to the topic of climate change in high school through the movie, “An Inconvenient Truth”, and since then the issue has been weighing heavily on my mind. A few years ago I became aware of a solution to climate change called geoengineering. Encyclopaedia Britannica defines geoengineering as, “the large-scale manipulation of a specific process central to controlling Earth’s climate for the purpose of obtaining a specific benefit.”

There are forty proposed methods, but the two primary methods used are Carbon Dioxide Reduction (CDR) and Solar Radiation Management (SRM). CDR deals with reducing the amount of carbon dioxide in the air through natural means such as planting more trees and algae, and increasing carbon in soils. I agree with this process because although we are tampering with the ecosystem of the planet, we are not introducing new things into it. With fast fluctuating climate changes, I understand why the demand to be able to control the weather is an issue. I agree with certain methods like CDR to help strengthen our planet so that it can defend itself, much like strengthening the immune system of a human being.

Example of Carbon Reduction (Tree Planting) Source: Flickr Commons

Example of Carbon Reduction (Tree Planting)
Source: Flickr Commons

On the other hand, we have SRM that is reducing the amount of solar radiation reaching the Earth’s surface. This method is done by introducing nanoparticles such as sulphate, barium, and aluminum into the atmosphere. The health effects from these types of metals over a long period of time are unknown, which is my main problem with this method. Volcanoes release sulphate naturally, but with such a high amount being pumped into our skies we don’t know the effect that it will have on our respiratory system, and the respiratory system of animals as well. Also, other particles involved such as aluminum have been related to human diseases such as Alzheimer’s disease. Another concern is the filtering out of many positive effects of sunlight such as Vitamin D.

Example of Solar Radiation Management (Chemical Trails) Source: Flickr Commons

Example of Solar Radiation Management (Chemical Trails)
Source: Flickr Commons

At this point, with the SRM aspect, I feel like it is more of an experiment that we cannot afford to gamble with. Other pressing issues such as genetically modified foods still leave us with the freedom of choice, whereas with geoengineering we are all participants whether we like it or not.

Video on Solar Radiation Management
Source: Youtube
Author: dschnei333

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– Jenna Bains

Something is going on while you are sleeping

Man sleeping. source: google image(free to share)

We spend about a third of our lives sleeping, and it is considered as an activity as crucial to our health and well-being as eating. Sleep makes us improve our mood and feel more energized. However, there are a lot of unknown information and things going on while we are at rest.

First, what is going on while you are asleep? When we’re sleeping, neurons in the brain fire nearly as much as they do while we are awake. That means whatever happening during our sleeping hours is quite important to a number brain and cognitive functions.

These are some reasons why you need enough sleep and they describe what our brains do while we are asleep – and it suggest you to get some shut-eye tonight.

1. Rememers / Learns how to perform physical activities.

Your brain stores information into a long-term memory in sleep spindles, which signal processes that refresh our memories. This process help storing information specifically related to physical tasks, such as sports, driving, and dancing. These short-term memories are transferred from the motor cortex to the temporal lobe, where they become long-term memories.

2. Create and strengthen memories

Location of hippocampus in the brain source: wikipedia common

While you are asleep, the brain keeps forming new memories linking them from old ones to more recent memories. This process happens during both REM and non-REM sleep periods. Lack of sleep can cause a significant effect on the hippocampus, and affect in memory creation and consolidation. Due to this fact, all nighter would lose their ability to learn new study materials.

3. Decision making

Decision making: where to go sources: google image( free to share)

The brain can process information and prepare for actions during sleep. A recent study found that the brain processes complex stimuli while we are asleep, and utilize this information to make some decisions while we are awake.

4. Clears out toxins

Research at the Univiersity of Roschester found that during the sleep, the brains of mice flush out damaging molecules associated with neurodegeneration, which could potentially have the effect of accelerating diseases like Parkinson’s and Alzheimer’s. Therefore, our brains would not have enough time to flush out toxins if we do not get adequate time of sleep.

Parkinson’s disease effect on various parts of brain. sources: google image(free to share)

Why do we need sleep? and What is going on in our brains during the sleep?

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Jack Yoon

Who said you can’t see bright stars in the deep ocean?

 

Euprymna scolopes by MattiasOrmestad

A photo of a Bobtail squid,  Euprymna scolopes, performing bioluminescence. It’s underside is brightly lit by its symbiotic bacteria V.fischeri. Photo by Mattias Ornestad on kahikai.org

Euprymna scolopes, commonly known as the Bobtail squids, are found around the Hawaiian Islands. Additionally, they’re about 4.5cm and has one other amazing fact: they have an indirect ability to perform bioluminescence, which is the production or emission of light by living organisms.  To be exact, the Bobtail squids don’t produce this phenomenon, it is the bacteria residing in these squids that produce this light. Together they can perform the largest symphony of dancing blue stars in the ocean.

The bacteria, Vibrio fischeri, is a symbiont that lives in the mantle of the Bobtail squids. The squids acquire this bacteria after they are hatched. These symbionts live in the deepest tract of the mantle and they produce the light source depending on the seawater environment, sensed through the squids’ pores. Furthermore, the Bobtail squids expel around 90-95% of these bacteria every dawn. At dusk, the bacteria increase in population and emit light again from the mantle. Since Euprymna scolopes is a nocturnal species, it hunts for prey at night time. With the bacteria, the squids are able to perform counterillumination. This effect allows them to camouflage themselves by looking like the sky above or deep abyss to divert their predators’ attention.

Here’s a video from the United Kingdom Society for Applied Microbiology uploaded by Siouxsie Wiles on YouTube. It explains how the Bobtail squids and the bacteria interact.

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But here is the most astonishing hypothesis about the symbiotic relationship: the squids themselves can adjust the intensity of the light produced by their dependents.

Research tested this hypothesis and found two possible theories. Firstly, the squids may be controlling their oxygen intake to restrict the bacteria’s production of energy, thus resulting in dimmer or brighter illumination.  Secondly, the squids control light emission by using their ink sac as an iris to restrict light. Both processes cannot kill the bacteria but only limit its emission. Unfortunately, biologists couldn’t explain the mechanism behind light intensity control since they could not visually see inside the mantle.

Aliivibrio fischeri (toxita.cz)

A photo of the bacteria, Vibrio fischeri, which provides the Bobtail squid bioluminescence, in a petri dish. Photo from toxita.cz.

Biologists are trying to find out how these bacteria communicate with its host. There still remain many unanswered questions. For example, how do the squids know how much V. fischeri to expel? What happens if we remove these symbiotic bacteria from their hosts? How do the squids know when to stop before killing the bacteria?

With further research, they hope to understand how bacterial cells communicate with human cells using Bobtail squids as their model. Scientists wish to find ways to distinguish harmful bacteria versus those that help regulate our body. By understanding how V.fischeri functions inside the squids, we could produce antibiotics that only pinpoint the harmful bacteria in our body and find ways to disrupt these bacteria from causing us sicknesses.

– Alison Fung

 

 

 

 

Can a mother have different DNA than her children?

In 2002, Lydia Fairchild was told that she was not the mother of her children. Prior to this, she had applied for child support from the children’s father, and DNA tests were performed in order to verify that both parents were in fact, the children’s biological parents. Although the DNA of the children matched that of the father, a bizarre discovery was made: the children’s DNA did not match that of Fairchild. Instead, she became the subject of an investigation into possible welfare fraud, and was interrogated by Social Services about her identity and who the children’s real mother was. Could the DNA testing have been incorrect? Is it a possibility that a mother’s DNA doesn’t match that of her children?

A chimeric mouse (right) with pups (left). The patches of two differing fur colours represent two genetically distinct cell populations. Source: NIMH’s Transgenic Core Facility

In the same year, a study came out in the New England Journal of Medicine about another woman facing disputed maternity over her children. The researchers of the study found that the woman had chimerism, a rare condition in which an individual is composed of genetically distinct cells. In these cases, it was due to the fusion of two zygotes, each with its own DNA, resulting in offspring composed of two genetically distinct populations of cells. It was later found that Fairchild also had chimerism, and was able to keep custody of her children.

For more on chimerism and Lydia Fairchild’s case:

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Source: Amutanga on YouTube

In summary, chimerism can cause a mother to have different DNA than her children, and it is fascinating to consider that a person can have two distinct sets of DNA. Scientists have recently been able to make a chimeric sheep whose blood contained 15% human cells and 85% sheep cells, which has implications for the production of transplant organs. It is interesting to consider where the field of chimerism will take us, but of course, not without safety and ethical concerns.

 

 

 

 

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“Turbocharged” Photosynthesis – Wait what?!

Plants convert the sun’s energy into food. Source: Wikipedia Commons

Photosynthesis is a process that plants and other living organisms use to convert carbon dioxide, water and light energy into food. Sounds pretty amazing, right? But that’s only the start.  Photosynthesis single-handedly supplies all the organic compounds and nearly all the energy that is needed for life on Earth. Simply put, without photosynthesis we would not be alive today. In recent years, a question that has often been asked is whether photosynthesis can be tweaked such that the process becomes faster and more efficient.

-Click here for all the intricate details of photosynthesis! Also, the process is illustrated nicely in this short animated film:

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Micrograph of a cyanobacterial species; Synechococcus elongatus. Source: L.A. Sherman and D.M. Sherman, Purdue University

Crucial to photosynthesis is an enzyme called Rubisco. This enzyme is required in the conversion of carbon dioxide to sugar. However, the Rubisco found in plants is inefficient. And so, a team of American and British biologists came up with the idea to “borrow” genes for Rubisco from a cyanobacterial species, called Synechococcus elongates, and genetically engineer them into plants. Formerly known as blue-green algae, cyanobacteria specialize in photosynthesis. Consequently, researchers claim that by meddling with Rubisco in crops, photosynthesis can increase in efficiency by up to 60%.

 

In the aforementioned experiment, published in Nature, the team of researchers transferred bacterial genes and proteins, including Rubisco, into the tobacco plant, Nicotiana tabacum. As a result, this new hybrid plant could convert carbon dioxide to sugar faster than normal strains of the tobacco plant. When asked how her team of scientists was able to accomplish this feat where other teams had failed before, biochemist Maureen Hanson at Cornell University pointed to the fact that her team also transferrd additional proteins to assist the foreign Rubisco.

tobaccoplant

A bacterial enzyme was delivered to a sample of Tobacco Plant; Nicotiana tabacum. Source: Rothamsted Research

With crop production technology being a hot field of research, the implications of this study are immensely important. While human population continues to increase at staggeringly fast rates, there are continuously more mouths to feed. “Hacked photosynthesis” may be one way to alleviate the looming problem.

You may be wondering… when will these super-efficient plants be in crop fields near you? Not as soon as you might think. While turbocharged photosynthesis works great in theory, in reality there are a few setbacks. One issue is that cyanobacterial Rubisco has a tendency to react with oxygen. Bacteria deal with this problem by incorporating a protective capsule, called a carboxysome, to ward off oxygen. However, plants lack this defensive shell and so the tobacco plant with bacterial Rubisco wastes significant amounts of energy. Naturally, scientists are currently working on ways for plants to create structures resembling bacterial carboxysomes.

cropfield

‘Turbo’ photosynthesis could redefine the way we farm crops. Source: Flickr commons, Uploader: Appe Plan

All in all, while the process of turbocharged photosynthesis has yet to be perfected, this scientific finding is a great leap in the direction of higher-yielding and faster-growing crops.

-Imran Mitha

 

Contact Lenses. Bye-bye Eye Sight

Do you wear contact lenses? I don’t. I don’t know how to order them, how to put them on, or how to clean them. But even though I have little to no knowledge on contact lenses, I do know this: Don’t sleep with them on!

About half of my friends wear contact lenses and at some point, I hear them say “I slept with my contact lenses on last night”. Guaranteed.

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The application of a contact lens. Source: Flickr Commons user suanie

At this point, some of you are probably thinking:

“Why do we say this?”

“What’s the reason for taking out contact lenses before bed?”

“What are the proper steps to cleaning them?”

Well, I am here to help answer these questions.

In a recent article published by CBC, ophthalmologist Tim Hillson addresses the fact that contact lenses prevent oxygen flow to the cornea, causing nutrient-providing blood vessels in the eye to expand. This makes the eye prone to infection. Leaving the contact lenses on over night allows bacteria build up that can penetrate the cornea.

There are 3 types of infection to the cornea:

Acanthamoeba keratitis: A rare infection caused by amoeba, often found in swimming pools, tap water, and hot tubs. May result in blindness.

Bacterial keratitis: An infection that proceeds rapidly. Caused by common bacteria like staphylococcuss aureus.

Fungal keratitis: An infection caused by a fungal organism. Usually involves pain in the eye.

Recently, Lian Kao, 23 year-old Taiwanese student became blind due to prolonged application of contact lenses. When I say prolonged – I mean 6 months! Kao did not remove her disposable contact lenses for 6 months straight, and even went swimming with them on. The cause of her blindness is said to be from Acanthamoeba (as described above), where amoeba ate her cornea during the course of 6 months.

An illustration of Amoeba proteus, by Joseph Leidy, 1879 − The organism that caused Lian Kao’s blindness. Rare but dangerous when infected. Source: Wikipedia

An illustration of Amoeba proteus, by Joseph Leidy, 1879 − The organism that caused Lian Kao’s blindness. Rare but dangerous when infected. Source: Wikipedia

Specialists say that the blindness caused by acanthamoeba is an extreme case, but they want the public to “realize the importance of using contact lenses as prescribed”. Well, I guess it is fair to say that Lian Kao learned it the hard way.

So how preventable are these infections? Easy. Just follow these 8 steps regularly.

  1. Wash and rinse hands with a mild non-cosmetic soap before handling contact lenses.
  2. Dry hands with a clean towel.
  3. It is a good idea to keep fingernails short and apply hair spray before you put in your contacts.
  4. Put on makeup after the contact lenses are in your eyes, and remove them before you remove your makeup.
  5. Always use disinfecting solutions that your eye care professional has recommended. Be aware that some eye products or eye drops are not safe for contact lens users.
  6. Never use tap water directly on the contact lenses, or put them in your mouth.
  7. Clean each contact by rubbing it gently with your index finger in the palm of your other hand.
  8. Clean contact lens case after every use, with either sterile solution or hot tap water and let it air dry. These cases should be replaced every three months.

Here is a video showing the steps, created by FramesDirect.com:

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Aside from these steps, I also recommend getting eye exams or check ups regularly. Although you are not guaranteed protection from those nasty infections, just remember, doing something is better than doing nothing.

And again, don’t forget to take them out before going to bed.

-Lilly Inoue